Conventional copper-based networks that rely on Category cable (e.g. CAT 5, 6 or 7) are limited in the amount of power they can deliver via Power over Ethernet (PoE) and over what distance they can provide this power due to the limitation of the 28 AWG wires that are present in the cable. Even though multiple 28 AWG wires can be combined in the cable to deliver power, the power dissipation increases markedly as the current is increased and as the distance increases.
Also constraining the amount of power that can be delivered are the national international building standards that limit cable voltages to under 60 V DC. Otherwise, cabling must be treated as standard electrical power wiring which requires compliance with certain safety standards and licensed personnel for installation.